#!/vobs/wds/swt/bin/perl

# Copyright (c) 2004, 2005 MySQL AB
# Use is subject to license terms
# 
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; version 2 of the License.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA

die "Usage: rgrep [-iredblLn] regexp filepat ...\n       rgrep -h for help\n"
    if $#ARGV < $[;

# Written by Piet van Oostrum <piet@cs.ruu.nl>
# This is really free software

# Mats Lidell added support for gzip.
# Mats Lidell added support for skipping line numbers.

$nextopt = 1;
$igncase = '';
$regpat = 0;
$links = 0;
$error = 0;
$skipbin = 1;
$havenl = 1;
$debug = 0;

do { $regexp = shift (@ARGV); } while &checkopt ($regexp);
$icreg = $igncase;
$igncase = '';

eval 'sub grep_file {
	    while (<F>) {
		$ln++;
		if (/$regexp/o' . $icreg .') {
			print "$file:$ln:" if $havenl;
			print "$_";
			print "\n" if substr($_, -1, 1) ne "\n";
		}
	    }
}';

for (@ARGV) {
    if (! &checkopt ($_)) {
        if ($igncase || $regpat || /[?*[]/ || ! -e) {
	    if ($regpat) {
		s/#/\\#/g;
		$_ = "#$_#";
	    } else { # translate File pattern into regexp
                $re = '#($|/)'; $save = $_;
	        while (/[[*?+()|.^$#]/) {
		    $re .= $`;
		    $c = $&;
		    $_ = $';
		    if ($c eq '*') { $c = '[^/]*'; }
		    elsif ($c eq '?') { $c = '[^/]'; }
		    elsif ($c eq '[') {
		    	if (/.\]/) { $c = "[$`$&"; $_ = $'; }
			else {
			    $error++;
			    printf stderr "Illegal filepattern %s\n", $save;
			}
		    } else { $c = "\\$c"; }
		    $re .= $c;
		}
		$_ = "$re$_\$#$igncase";
	    }
	    print "filepat: $_\n" if $debug;
            push (@filepat, $_);
	}
        else { push (@files, $_); print "file: $_\n" if $debug; }
    }
}

exit 1 if $errors ;

if ($#filepat < $[) {
    eval "sub in_pat {1;}" ;
}
else {
    $subtxt = 'sub in_pat { local ($f) = @_;';
    $or = "";
    for (@filepat) {
	$subtxt .= $or . '$f =~ m' . $_;
	$or = " || ";
    }
    $subtxt .= ';};1';

    if (! eval $subtxt) {
    	print $@;
    	exit 1;
    }
} 

@files = (".") if $#files < $[;

for $file (@files) {
    &do_grep ($file);
}

sub do_grep {
    local ($file) = @_;
    local (*F, $ln, $f, $g, @dirfiles);
    if (-f $file) {
	if (open (F, $file)) {
	    if (-B F) { # binary file --  may be compressed/compacted/gziped
		if (($cx1 = getc(F)) eq "\377" && (getc(F) eq "\037")) {
		    open (F, "uncompact < $file|");
		    if ($skipbin && -B F) { close (F); return; }
		}
		elsif ($cx1 eq "\037" && (($cx2 = getc(F)) eq "\235")) {
		    open (F, "uncompress < $file|");
		    if ($skipbin && -B F) { close (F); return; }
		}
		elsif ($cx1 eq "\037" && $cx2 eq "\213") {
		    open (F, "gzip -d < $file|");
		    if ($skipbin && -B F) { close (F); return; }
		}
		elsif ($skipbin) {
		    close (F); return;
		}
	    }
	    print "Reading $file\n" if $debug;
	    &grep_file;
	} else {
	    print stderr "Cannot open $file\n";
	}
    }
    elsif (-d $file) {
	print "Entering $file\n" if $debug;
	if (opendir (F, $file)) {
	    @dirfiles = readdir (F);
	    closedir (F);
	    for $f (@dirfiles) {
		next if ($f eq '.' || $f eq '..');
		$g = "$file/$f";
		next if (-l $g && ($links < 1 || $links == 1 && -d $g));
		if (-f $g && &in_pat ($g) || -d _) {
		    &do_grep ($g);
		}
	    }
	} else {
	    print stderr "Can't open $file\n";
	}
    }
}

sub checkopt {
    local ($_) = $_[0];
    if (/^-/ && $nextopt) {
        $nextopt = 1;
	@opt = split (/-*/,$_); shift (@opt);
    	for $opt (@opt) {
	    if ($opt eq 'i') { $igncase = 'i'; }
	    elsif ($opt eq 'd') { $debug = 1; }
	    elsif ($opt eq 'l') { $links = 1; }
	    elsif ($opt eq 'L') { $links = 2; }
	    elsif ($opt eq 'b') { $skipbin = 0; }
	    elsif ($opt eq 'r') { $regpat = 1; }
	    elsif ($opt eq 'e') { $nextopt = 0; }
	    elsif ($opt eq 'n') { $havenl = 0; }
	    elsif ($opt eq 'h' || $opt eq 'H') { & help; }
	    else { $error++; printf stderr "Unknown option -%s\n", $opt; }
	}
    	return 1;
    }
    $nextopt = 1;
    return 0;
}

sub help {
    print <<'HELP'; exit 0;
Usage: rgrep [-iredblL] regexp filepat ...
  regexp = perl regular expression to search
  filepat ... = a list of files and directories to be searched or
      file patterns to match filenames.
      filepat will be interpreted as file or directory name if it exists
      as such, and does not contain the metacharacters [ ] ? or *. After
      the options -i and -r all filepats will be considered patterns.
      rgrep will search all files in any of the directories given (and its
      subdirectories) that match any of the filepats, except binary files.
      Compressed files will be searched in uncompressed form.
      Note: filepats may contain / contrary to find usage.
  -b  Don't skip binary files.
  -i  Ignore case, either in the regexp or in filename matching (depending
      on the location). Before the regexp only applies to the regexp,
      otherwise to the filepats following it.
  -r  The following filepats are treated as real perl regexps rather than
      shell style filename patterns. In this case / is not a special
      character, i.e. it is matched by . and matching is not anchored (you
      must supply ^ and $ yourself). E.g. a.b matches the file /xa/by/zz.
  -l  Do follow symbolic links only for files (default is do not follow).
  -L  Do follow symbolic links for files and directories.
  -e  Do not interpret following argument as option. Useful if regexp or
      filepat starts with a -.
  -d  Debugging: Give a lot of output on what happens.
  -n  Don't precede each line by its relative line number in the file.
  -h  print this message and exit.
Piet van Oostrum <piet@cs.ruu.nl>
HELP
}
